Revert "core/txpool/legacypool: handle missing head in reset (ethereu…

…m#27479)"

This reverts commit e9686ce.

core/txpool/legacypool/legacypool.go

@@ -1283,14 +1283,6 @@ func (pool *LegacyPool) reset(oldHead, newHead *types.Header) {
 					"old", oldHead.Hash(), "oldnum", oldNum, "new", newHead.Hash(), "newnum", newNum)
 				// We still need to update the current state s.th. the lost transactions can be readded by the user
 			} else {
-				if add == nil {
-					// if the new head is nil, it means that something happened between
-					// the firing of newhead-event and _now_: most likely a
-					// reorg caused by sync-reversion or explicit sethead back to an
-					// earlier block.
-					log.Warn("New head missing in txpool reset", "number", newHead.Number, "hash", newHead.Hash())
-					return
-				}
 				for rem.NumberU64() > add.NumberU64() {
 					discarded = append(discarded, rem.Transactions()...)
 					if rem = pool.chain.GetBlock(rem.ParentHash(), rem.NumberU64()-1); rem == nil {